73S1217F Maxim, 73S1217F Datasheet - Page 73

• Manufacturer Part Number: 73S1217F
• Description: The Teridian 73S1217F is a self-contained SoC smart card reader IC that is an ideal solution for any USB-connected ISO 7816 design
• Manufacturer: Maxim

Keypad Scan Time Register (KSIZE): 0xD5
This register is not applicable when HWSCEN is not set. Unused row inputs should be connected to
VDD.
Keypad Column LS Scan Order Register (KORDERL): 0xD6
In the KORDERL and KORDERH registers, Column Scan Order(14:0) is grouped into 5 sets of 3 bits
each. Each set determines which column (COL(4:0) pin) to activate by loading the column number into
the 3 bits. When in HW_Scan_Enable mode, the hardware will step through the sets from 1Col to 5Col
(up to the number of columns in Colsize) and scan the column defined in the 3 bits. To scan in sequential
order, set a counting pattern with 0 in set 0, and 1 in set 1,and 2 in set 2, and 3 in set 3, and 4 in set 4.
The firmware should update this as part of the interrupt service routine so that the new scan order is
loaded prior to the next key being pressed. For example, to scan COL(0) first, 1Col(2:0) should be
loaded with 000’b. To scan COL(4) fifth, 5Col(2:0) should be loaded with 100’b.
Rev. 1.2
MSB
KORDERL.7
KORDERL.6
KORDERL.5
KORDERL.4
KORDERL.3
KORDERL.2
KORDERL.1
KORDERL.0
KSIZE.7
KSIZE.6
KSIZE.5
KSIZE.4
KSIZE.3
KSIZE.2
KSIZE.1
KSIZE.0
Bit
–
Bit
MSB
3COL.1
ROWSIZ.2
ROWSIZ.1
ROWSIZ.0
COLSIZ.2
COLSIZ.1
COLSIZ.0
–
Symbol
Symbol
3COL.1
3COL.0
2COL.2
2COL.1
2COL.0
1COL.2
1COL.1
1COL.0
3COL.0
–
–
ROWSIZ.2
Defines the number of rows in the keypad. Maximum number is 6 given
the number of row pins on the package. Allows for a reduced keypad size
for scanning.
Defines the number of columns in the keypad. Maximum number is 5
given the number of
keypad size for scanning.
Column to scan 3
Column to scan 2
Column to scan 1
2COL.2
Table 74: The KORDERL Register
Table 73: The KSIZE Register
ROWSIZ.1
2COL.1
rd
nd
st
.
0x00
.
(lsb’s).
ROWSIZ.0 COLSIZ.2 COLSIZ.1 COLSIZ.0
column pins on the package. Allows for a reduced
2COL.0
Function
Function
1COL.2
0x00
1COL.1
1COL.0
LSB
LSB
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